OPRV - Late Valve, Late Block early hsg?
08-14-2004, 11:33 PM
#1
Race Director
Thread Starter
OPRV - Late Valve, Late Block early hsg?
Hey,
Anybody try this combo.
late block, late OPRV, and an early oil filter housing.
It looks like it will fit, but the early housing's hole is little on the small side.
Think it will work.
Anybody try this combo.
late block, late OPRV, and an early oil filter housing.
It looks like it will fit, but the early housing's hole is little on the small side.
Think it will work.
08-15-2004, 02:31 AM
#3
Race Director
Thread Starter
Thread sizes are the same, and the early housing "fits" on the late block and with a late OPRV, but I the bore of the early housing is couple mm smaller resulting in a little less clearance. Not sure how that will impact operation. That is why I am asking.
08-15-2004, 08:14 AM
#4
Drifting
I am using the late 1987 housing on a 1983(non-P/S crankshaft) block, with 86' OPRV piston and longer spring. If you can muscle the OPRV cap to thread into the housing- you will get perfect oil pressure...even on a rebuild! My re-machined 83' engine got instant oil pressure the moment the key lighted the spark plugs. Plus, I forgot to prime the bone-dry dry oil pump! The late 86' grooved-piston OPRV is a better design, and is finished to move smoothly inside the oil cooler bore with minimal oil present. The longer, stronger, 130mm forged spring assures oil pressure with a whopping 40lb spring rate.
08-15-2004, 02:36 PM
#5
Race Director
Thread Starter
Dilberto,
Thanks for info, but my case is completled reversed. Late engine block, late OPRV and early 86 housing. These are the parts I have that I want to use together. It is long story as to why I have these parts, but I am keeping the block and to use a late block I need the late OPRV Which I have. My issue is with early oil filter housing. I would like to not need to search for another one...
... PS don't ask what happened to the late oil filter housing?
Thanks for info, but my case is completled reversed. Late engine block, late OPRV and early 86 housing. These are the parts I have that I want to use together. It is long story as to why I have these parts, but I am keeping the block and to use a late block I need the late OPRV Which I have. My issue is with early oil filter housing. I would like to not need to search for another one...
... PS don't ask what happened to the late oil filter housing?
08-15-2004, 05:07 PM
#6
Race Director
Hmm, you might want to measure the on the filter-housing and the diameter of the OPRV at that spot. I've tried fitting an later OPRV to an earlier block & housing and it wouldn't fit.
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08-16-2004, 11:11 AM
#8
Race Director
Thread Starter
What I really need is a LATE Oil Filter housing. I have late block and late OPRV. And no the early 1-piece valves do not fit this block. I check that and there is no chance
Dilberto. Nope... I have an early housing already. I just am not sure it will work.
Dilberto. Nope... I have an early housing already. I just am not sure it will work.
08-16-2004, 12:41 PM
#9
Three Wheelin'
David Floyd has a late housing on an early block, and he is using the early OPRV. I believe the housings are interchangeable, but not the OPRV's. They are specific to the block. The length is different, but the threads are the same.
08-19-2004, 04:29 PM
#12
Hates Family Guy
Rennlist Member
Rennlist Member
I would if I could. I dug through all the extra engine parts I have, and I don't have anything with a late OPRV or housing. I found about 3 early ones, with two different part numbers.
If what Keith says above is correct, that the threads are the same, and if the thickness of the housing at that point is the same, then I'd think you're good to go.
Found this in another thread. Ignore the fact he's talking about an '86, it still shows an early and late OPRV.
Just from looking at the pic the threads look the same.
If what Keith says above is correct, that the threads are the same, and if the thickness of the housing at that point is the same, then I'd think you're good to go.
Found this in another thread. Ignore the fact he's talking about an '86, it still shows an early and late OPRV.
Originally Posted by Granite944
Figure A is the 944 107 035 11 valve.
Fig. B is the 944 107 035 01 valve.
You should be using valve Fig. A as a replacement for your '86
The longer valve (fig. B) is replacement for '87 and newer.
Fig. B is the 944 107 035 01 valve.
You should be using valve Fig. A as a replacement for your '86
The longer valve (fig. B) is replacement for '87 and newer.
Just from looking at the pic the threads look the same.
08-19-2004, 04:39 PM
#13
Race Director
Thread Starter
Yep the threads are the same and the new valve fits in the old housing, but there is a little less clearance for the small hole in the valve.
Now will that tigher clearance cause a problem with valve operation?
That I don't know and is why I am asking.
Now will that tigher clearance cause a problem with valve operation?
That I don't know and is why I am asking.
08-19-2004, 08:49 PM
#14
Hates Family Guy
Rennlist Member
Rennlist Member
Well, let's say it's a cold morning and you're running dino oil. The valve would open all the way, and the maximum amount of oil would flow through the valve. The oil would have to flow out the 4 holes on the side, and flow up the outside of the valve to the housing. Everything is normal, until it gets to the housing, which has a slightly smaller inside diameter. There's still the cutout that is the same size, just the other 3/4 or so of the circle. I wouldn't think it would be a problem, expecially living in Arizona and running synthetic. One test might be to see how the alignment tool fits. If it fits alright I'd give it a try. Or I guess I should ask first, is this for the spec car or one of the others?
08-19-2004, 08:52 PM
#15
Three Wheelin'
I would have to say, no it won't work. If you look at the PET for 1985 or older 944, it specifies a part number for the filter housing and only the part number for the single piece replacement for the old-style OPRV. If you look at the PET for a 1986 or newer 944, it specifies a later part number for the filter housing, and both the early-style and late-style OPRV part numbers. This suggests that you can use a late-style housing with an early-style block and OPRV, but NOT the other way around, which is what you want to do.
Informed speculation. YMMV.
Informed speculation. YMMV.